1. Field of the Invention
This invention relates to a method of making a shoe, more particularly, a method in which a front portion of an upper is stitched directly to an outsole and a rear portion of the upper is sewn to a midsole.
2. Description of the Related Art
A typical shoe construction, well known as the Opanka construction, includes an upper having a bottom open end stitched directly to the periphery of an outsole without any midsole attached to the upper. While such a shoe construction provides good flexibility, due to the absence of the midsole, it does not have sufficient strength at its heel region so that it can be deformed easily, especially when the user who wears the shoe takes part in dynamic activities.
In order to alleviate the aforesaid problem, an improved method of constructing a shoe is suggested in U.S. Pat. No. 6,029,301. The method includes stitching the bottom end of a front portion of an upper to the outer peripheral end of a front portion of an outsole through pre-punched needle holes provided in the front portions of the upper and the outsole, and lasting the bottom end of a rear portion of the upper to a midsole by means of a heel lasting machine followed by the step of securing the midsole to the outsole. The shoe constructed by this method not only provides enhanced strength at the heel region to alleviate the deformation problem but also possesses good flexibility. However, inconveniences are caused due to the use of the heel lasting machine. In addition, since the upper is made of a flexible material, the heel lasting machine would deform the front portion of the upper and would cause misalignment of the pre-punched needle holes in the upper and the outsole if the front portion of the upper is stitched to the outsole after the rear portion is lasted. To avoid the misalignment problem, the stitching operation is carried out prior to the lasting operation by using a complicated hinged last which has a stationary front section and a movable heel section. The use of such a hinged last complicates the method of constructing the shoe.
An object of the present invention is to provide a simple method of making a shoe which eliminates the problem encountered in the prior art disclosed in the above-mentioned U.S. Patent.
According to the present invention, a method of making a shoe, comprises: (a) preparing an upper which includes an open top end, an open bottom end, an enclosing wall extending from the top end to the bottom end, the enclosing wall having a front section and a rear section, the front section having a front stitching margin, the rear section having a rear stitching margin; (b) preparing an outsole having a front section and a rear section; (c) preparing a midsole including at least a heel section; (d) stitching the rear stitching margin to the midsole; (e) inserting a last into the upper; (f) gluing and attaching the rear section of the outsole to the rear stitching margin and the midsole; and (g) stitching the front stitching margin to the front section of the outsole.